Football helmet shell



FIG. 1 is a front and right side perspective view of a football helmet shell showing my new design;

FIG. 2 is a front view thereof;

FIG. 3 is a left side view thereof;

FIG. 4 is a top plan view thereof;

FIG. 5 is a rear view thereof; and,

FIG. 6 is a bottom plan view thereof.

The details shown in broken lines in FIG. 1 form no part of the claimed design. 

CLAIM The ornamental design for a football helmet shell, as shown and described. 